Hello ladies and gentlemen, hope yall are having a great day.I have a little problem and i was wondering if anyone could help.I have a pmdg-posky 747 merge and i noticed when on approach and i set my flaps to 5, the nose pitches down excessively, sometimes down to 3-5 degrees, i know i'm at the right speed as i'm following the flap indicator settings on the pfd. Also when i look at the flaps from an exterior view, they seem to be at least on the 20 degree setting, even though the display shows it's at 5 degrees. This is what the flaps section of the merge looks like...does anyone have an alternate setting?[flaps.0]type = 1 // Trailing edgespan-outboard = 0.8 // 0.0 .. 1.0extending-time = 25 // secondsflaps-position.0 = 0 // pseudo-degreesflaps-position.1 = 0.00,280 // 1 - no TEflaps-position.2 = 25.0,260 // 5flaps-position.3 = 27.5,240 // 10flaps-position.4 = 30.0,230 // 20flaps-position.5 = 31.5,205 // 25flaps-position.6 = 33.0,180 // 30lift_scalar = 1.0drag_scalar = 0.1pitch_scalar= 1.0system_type = 1 //Hydraulic[flaps.1]type = 2 // Inboard/midboard leading edgespan-outboard = 0.53333 // 0.0 .. 1.0extending-time = 12 // secondsflaps-position.0 = 0 // pseudo-degreesflaps-position.1 = 1.0 // 1damaging-speed = 275 // KIASblowout-speed = 280 // KIASlift_scalar = 0.88drag_scalar = 1.54pitch_scalar= 1.0system_type = 1 //Hydraulic[flaps.2]type = 2 // Outboard leading edgespan-outboard = 0.2666 // 0.0 .. 1.0extending-time = 10 // secondsflaps-position.0 = 0 // pseudo-degreesflaps-position.1 = 0.0 // 1 - no effectflaps-position.2 = 5.0 // 5damaging-speed = 255 // KIASblowout-speed = 260 // KIASlift_scalar = 1.0drag_scalar = 1.0pitch_scalar= 1.0system_type = 1 //Hydraulic[flaps.3]type = 1 // Modelspan-outboard = 0.7extending-time = 60flaps-position.0 = 0.0flaps-position.1 = 1.0flaps-position.2 = 5.0flaps-position.3 = 10.0flaps-position.4 = 20.0flaps-position.5 = 25.0flaps-position.6 = 30.0lift_scalar = 0.0drag_scalar = 0.0pitch_scalar= 0.0system_type = 1 Thanks in advance

Pitching down when you apply flap probably means that the flaps are generating too much lift at the rear of the wing on deployment for the speed that you're travelling at. This can be controlled by varying the 'lift_scalar=' parameter in the flap section that governs the trailing edge of the wing (type=1) - [flaps.0] in this case. So you might change the value of 1.0 in your [flaps.0] section to 0.5, which then generates half the lift from the flaps, and see what that does to your attitude in the sim. Vary up or down in increments of 0.1 until you're happy with what you see.Don't forget to back up your aircraft.cfg file before you do anything!;)

When simulator aircraft pitch up on flap application, as a lot of them do, it's one of the things that annoys me, as the vast majoirty of aircraft will indeed pitch down with flaps.So pitching down with flaps is fairly realistic actually, because the wing generates more lift and the centre of lift moves rearwards too, both of which make the tail-down force of the elevators less effective until re-trimmed. We've seen this demonstrated in a few accidents in recent years, where tailplane icing has only been discovered when this phenomenon kicks in as the flaps are lowered on approach, the discovery of which has often been too late to affect a recovery from the pitch down because the elevator leading edges were iced up and stalled in the flap's airflow.If I were you, I would tweak the flap lift scalar, but not so much as to remove the effect totally, because pitch down with flaps is realistic to some degree.Al

When simulator aircraft pitch up on flap application, as a lot of them do, it's one of the things that annoys me, as the vast majoirty of aircraft will indeed pitch down with flaps.

True for the Piper Cherokee, for example (and the vast majority of aircraft as you said), but wrong for the almighty Twin Otter. The "Stiff legs" will actually pitch up on flaps application and pitch down on flaps removal. The manual states that you should actually try to push/pull the yoke (and help yourself with trim) when lowering/raising flaps. It is even considered on the flight training as a manoeuvre to practice as the first 10

True for the Piper Cherokee, for example (and the vast majority of aircraft as you said), but wrong for the almighty Twin Otter.

As you point out, that is why I wrote 'the vast majority of aircraft' and not 'all aircraft' :( You should try flying a few fancy gliders with negative flap settings, that's always fun :(

Al,The method I suggested is one I routinely use for setting flap lift in the most realistic way; I wasn't suggesting that the effect should be removed entirely. In fact you absolutely shouldn't do this because if you remove the flap lift altogether, then the plane is likely to stall on approach because the angle of attack will get too high. The point is to adjust it incrementally until the behaviour mirrors what really happens. In this way you can get a FD to mirror what a 737 or a Twotter does. If you have a plane which pitches down at the first notch of flaps when you're setting up for an approach, then the FD design needs looking at, I would suggest. This is especially so if you get to the stage in say a 757 where you're at approach speed at the correct flap setting, and the nose is pointing down rather than where it should be.;)

I'm not the one you should be addressing. I was trying to help the OP just as you were, none of my FS aircraft need fixing. :( Al

You made the comment; I thought you'd be interested in the logic. :(

Thank you guys for the responses. Very true most aircraft pitch down when flaps are extended but when a 620,000lbs B744 @ 200KIAS is pitching down 3-5 degrees below zero with only flap 5 extended...kinda weird. I wish i had a reference to tweak the lift scalar to. If anyone does have flap settings that work well, please let me know if you can help. I will go look on the pmdg & posky forums again, though i doubt i'll find much as neither of them support the merge.ThanksMr W

hey waly87, reduce the "flap_sclar" below 1 . try it. then try again landing. so you will be saw your nose up.but i am newbie about flight dynamics. which flaps effect them i don t know (flap.0 or flap.1 or flap.2).If anybody answer wal87's question maybe we can found an a way to correct the flight dynamic of the planehow does the 'lift_scalar' section at flap setting that effect the airplane dynamic?

Edited January 29, 201214 yr by ddk